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<h1 class="title">textedit.cpp 示例文件</h1>
<span class="subtitle">tools/customcompleter/textedit.cpp</span>
<!-- $$$tools/customcompleter/textedit.cpp-description -->
<div class="descr"> <a name="details"></a>
<pre class="cpp">

  <span class="comment">/****************************************************************************
  **
  ** Copyright (C) 2016 The Qt Company Ltd.
  ** Contact: https://www.qt.io/licensing/
  **
  ** This file is part of the examples of the Qt Toolkit.
  **
  ** $QT_BEGIN_LICENSE:BSD$
  ** Commercial License Usage
  ** Licensees holding valid commercial Qt licenses may use this file in
  ** accordance with the commercial license agreement provided with the
  ** Software or, alternatively, in accordance with the terms contained in
  ** a written agreement between you and The Qt Company. For licensing terms
  ** and conditions see https://www.qt.io/terms-conditions. For further
  ** information use the contact form at https://www.qt.io/contact-us.
  **
  ** BSD License Usage
  ** Alternatively, you may use this file under the terms of the BSD license
  ** as follows:
  **
  ** &quot;Redistribution and use in source and binary forms, with or without
  ** modification, are permitted provided that the following conditions are
  ** met:
  **   * Redistributions of source code must retain the above copyright
  **     notice, this list of conditions and the following disclaimer.
  **   * Redistributions in binary form must reproduce the above copyright
  **     notice, this list of conditions and the following disclaimer in
  **     the documentation and/or other materials provided with the
  **     distribution.
  **   * Neither the name of The Qt Company Ltd nor the names of its
  **     contributors may be used to endorse or promote products derived
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  **
  ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  ** &quot;AS IS&quot; AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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  ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.&quot;
  **
  ** $QT_END_LICENSE$
  **
  ****************************************************************************/</span>

  <span class="preprocessor">#include &quot;textedit.h&quot;</span>
  <span class="preprocessor">#include &lt;QCompleter&gt;</span>
  <span class="preprocessor">#include &lt;QKeyEvent&gt;</span>
  <span class="preprocessor">#include &lt;QAbstractItemView&gt;</span>
  <span class="preprocessor">#include &lt;QtDebug&gt;</span>
  <span class="preprocessor">#include &lt;QApplication&gt;</span>
  <span class="preprocessor">#include &lt;QModelIndex&gt;</span>
  <span class="preprocessor">#include &lt;QAbstractItemModel&gt;</span>
  <span class="preprocessor">#include &lt;QScrollBar&gt;</span>

  TextEdit<span class="operator">::</span>TextEdit(<span class="type"><a href="qwidget.html">QWidget</a></span> <span class="operator">*</span>parent)
  : <span class="type"><a href="qtextedit.html">QTextEdit</a></span>(parent)<span class="operator">,</span> c(<span class="number">0</span>)
  {
      setPlainText(tr(<span class="string">&quot;This TextEdit provides autocompletions for words that have more than&quot;</span>
                      <span class="string">&quot; 3 characters. You can trigger autocompletion using &quot;</span>) <span class="operator">+</span>
                      <span class="type"><a href="../qtgui/qkeysequence.html">QKeySequence</a></span>(<span class="string">&quot;Ctrl+E&quot;</span>)<span class="operator">.</span>toString(<span class="type"><a href="../qtgui/qkeysequence.html">QKeySequence</a></span><span class="operator">::</span>NativeText));
  }

  TextEdit<span class="operator">::</span><span class="operator">~</span>TextEdit()
  {
  }

  <span class="type">void</span> TextEdit<span class="operator">::</span>setCompleter(<span class="type"><a href="qcompleter.html">QCompleter</a></span> <span class="operator">*</span>completer)
  {
      <span class="keyword">if</span> (c)
          <span class="type"><a href="../qtcore/qobject.html">QObject</a></span><span class="operator">::</span>disconnect(c<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="number">0</span>);

      c <span class="operator">=</span> completer;

      <span class="keyword">if</span> (<span class="operator">!</span>c)
          <span class="keyword">return</span>;

      c<span class="operator">-</span><span class="operator">&gt;</span>setWidget(<span class="keyword">this</span>);
      c<span class="operator">-</span><span class="operator">&gt;</span>setCompletionMode(<span class="type"><a href="qcompleter.html">QCompleter</a></span><span class="operator">::</span>PopupCompletion);
      c<span class="operator">-</span><span class="operator">&gt;</span>setCaseSensitivity(<span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>CaseInsensitive);
      <span class="type"><a href="../qtcore/qobject.html">QObject</a></span><span class="operator">::</span>connect(c<span class="operator">,</span> SIGNAL(activated(<span class="type"><a href="../qtcore/qstring.html">QString</a></span>))<span class="operator">,</span>
                       <span class="keyword">this</span><span class="operator">,</span> SLOT(insertCompletion(<span class="type"><a href="../qtcore/qstring.html">QString</a></span>)));
  }

  <span class="type"><a href="qcompleter.html">QCompleter</a></span> <span class="operator">*</span>TextEdit<span class="operator">::</span>completer() <span class="keyword">const</span>
  {
      <span class="keyword">return</span> c;
  }

  <span class="type">void</span> TextEdit<span class="operator">::</span>insertCompletion(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span><span class="operator">&amp;</span> completion)
  {
      <span class="keyword">if</span> (c<span class="operator">-</span><span class="operator">&gt;</span>widget() <span class="operator">!</span><span class="operator">=</span> <span class="keyword">this</span>)
          <span class="keyword">return</span>;
      <span class="type"><a href="../qtgui/qtextcursor.html">QTextCursor</a></span> tc <span class="operator">=</span> textCursor();
      <span class="type">int</span> extra <span class="operator">=</span> completion<span class="operator">.</span>length() <span class="operator">-</span> c<span class="operator">-</span><span class="operator">&gt;</span>completionPrefix()<span class="operator">.</span>length();
      tc<span class="operator">.</span>movePosition(<span class="type"><a href="../qtgui/qtextcursor.html">QTextCursor</a></span><span class="operator">::</span>Left);
      tc<span class="operator">.</span>movePosition(<span class="type"><a href="../qtgui/qtextcursor.html">QTextCursor</a></span><span class="operator">::</span>EndOfWord);
      tc<span class="operator">.</span>insertText(completion<span class="operator">.</span>right(extra));
      setTextCursor(tc);
  }

  <span class="type"><a href="../qtcore/qstring.html">QString</a></span> TextEdit<span class="operator">::</span>textUnderCursor() <span class="keyword">const</span>
  {
      <span class="type"><a href="../qtgui/qtextcursor.html">QTextCursor</a></span> tc <span class="operator">=</span> textCursor();
      tc<span class="operator">.</span>select(<span class="type"><a href="../qtgui/qtextcursor.html">QTextCursor</a></span><span class="operator">::</span>WordUnderCursor);
      <span class="keyword">return</span> tc<span class="operator">.</span>selectedText();
  }

  <span class="type">void</span> TextEdit<span class="operator">::</span>focusInEvent(<span class="type"><a href="../qtgui/qfocusevent.html">QFocusEvent</a></span> <span class="operator">*</span>e)
  {
      <span class="keyword">if</span> (c)
          c<span class="operator">-</span><span class="operator">&gt;</span>setWidget(<span class="keyword">this</span>);
      <span class="type"><a href="qtextedit.html">QTextEdit</a></span><span class="operator">::</span>focusInEvent(e);
  }

  <span class="type">void</span> TextEdit<span class="operator">::</span>keyPressEvent(<span class="type"><a href="../qtgui/qkeyevent.html">QKeyEvent</a></span> <span class="operator">*</span>e)
  {
      <span class="keyword">if</span> (c <span class="operator">&amp;</span><span class="operator">&amp;</span> c<span class="operator">-</span><span class="operator">&gt;</span>popup()<span class="operator">-</span><span class="operator">&gt;</span>isVisible()) {
          <span class="comment">// The following keys are forwarded by the completer to the widget</span>
         <span class="keyword">switch</span> (e<span class="operator">-</span><span class="operator">&gt;</span>key()) {
         <span class="keyword">case</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>Key_Enter:
         <span class="keyword">case</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>Key_Return:
         <span class="keyword">case</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>Key_Escape:
         <span class="keyword">case</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>Key_Tab:
         <span class="keyword">case</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>Key_Backtab:
              e<span class="operator">-</span><span class="operator">&gt;</span>ignore();
              <span class="keyword">return</span>; <span class="comment">// let the completer do default behavior</span>
         <span class="keyword">default</span>:
             <span class="keyword">break</span>;
         }
      }

      bool isShortcut <span class="operator">=</span> ((e<span class="operator">-</span><span class="operator">&gt;</span>modifiers() <span class="operator">&amp;</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>ControlModifier) <span class="operator">&amp;</span><span class="operator">&amp;</span> e<span class="operator">-</span><span class="operator">&gt;</span>key() <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>Key_E); <span class="comment">// CTRL+E</span>
      <span class="keyword">if</span> (<span class="operator">!</span>c <span class="operator">|</span><span class="operator">|</span> <span class="operator">!</span>isShortcut) <span class="comment">// do not process the shortcut when we have a completer</span>
          <span class="type"><a href="qtextedit.html">QTextEdit</a></span><span class="operator">::</span>keyPressEvent(e);

      <span class="keyword">const</span> bool ctrlOrShift <span class="operator">=</span> e<span class="operator">-</span><span class="operator">&gt;</span>modifiers() <span class="operator">&amp;</span> (<span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>ControlModifier <span class="operator">|</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>ShiftModifier);
      <span class="keyword">if</span> (<span class="operator">!</span>c <span class="operator">|</span><span class="operator">|</span> (ctrlOrShift <span class="operator">&amp;</span><span class="operator">&amp;</span> e<span class="operator">-</span><span class="operator">&gt;</span>text()<span class="operator">.</span>isEmpty()))
          <span class="keyword">return</span>;

      <span class="keyword">static</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> eow(<span class="string">&quot;~!@#$%^&amp;*()_+{}|:\&quot;&lt;&gt;?,./;'[]\\-=&quot;</span>); <span class="comment">// end of word</span>
      bool hasModifier <span class="operator">=</span> (e<span class="operator">-</span><span class="operator">&gt;</span>modifiers() <span class="operator">!</span><span class="operator">=</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>NoModifier) <span class="operator">&amp;</span><span class="operator">&amp;</span> <span class="operator">!</span>ctrlOrShift;
      <span class="type"><a href="../qtcore/qstring.html">QString</a></span> completionPrefix <span class="operator">=</span> textUnderCursor();

      <span class="keyword">if</span> (<span class="operator">!</span>isShortcut <span class="operator">&amp;</span><span class="operator">&amp;</span> (hasModifier <span class="operator">|</span><span class="operator">|</span> e<span class="operator">-</span><span class="operator">&gt;</span>text()<span class="operator">.</span>isEmpty()<span class="operator">|</span><span class="operator">|</span> completionPrefix<span class="operator">.</span>length() <span class="operator">&lt;</span> <span class="number">3</span>
                        <span class="operator">|</span><span class="operator">|</span> eow<span class="operator">.</span>contains(e<span class="operator">-</span><span class="operator">&gt;</span>text()<span class="operator">.</span>right(<span class="number">1</span>)))) {
          c<span class="operator">-</span><span class="operator">&gt;</span>popup()<span class="operator">-</span><span class="operator">&gt;</span>hide();
          <span class="keyword">return</span>;
      }

      <span class="keyword">if</span> (completionPrefix <span class="operator">!</span><span class="operator">=</span> c<span class="operator">-</span><span class="operator">&gt;</span>completionPrefix()) {
          c<span class="operator">-</span><span class="operator">&gt;</span>setCompletionPrefix(completionPrefix);
          c<span class="operator">-</span><span class="operator">&gt;</span>popup()<span class="operator">-</span><span class="operator">&gt;</span>setCurrentIndex(c<span class="operator">-</span><span class="operator">&gt;</span>completionModel()<span class="operator">-</span><span class="operator">&gt;</span>index(<span class="number">0</span><span class="operator">,</span> <span class="number">0</span>));
      }
      <span class="type"><a href="../qtcore/qrect.html">QRect</a></span> cr <span class="operator">=</span> cursorRect();
      cr<span class="operator">.</span>setWidth(c<span class="operator">-</span><span class="operator">&gt;</span>popup()<span class="operator">-</span><span class="operator">&gt;</span>sizeHintForColumn(<span class="number">0</span>)
                  <span class="operator">+</span> c<span class="operator">-</span><span class="operator">&gt;</span>popup()<span class="operator">-</span><span class="operator">&gt;</span>verticalScrollBar()<span class="operator">-</span><span class="operator">&gt;</span>sizeHint()<span class="operator">.</span>width());
      c<span class="operator">-</span><span class="operator">&gt;</span>complete(cr); <span class="comment">// popup it up!</span>
  }

</pre>
</div>
<!-- @@@tools/customcompleter/textedit.cpp -->
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